The Children, Schools and Families Secretary was speaking in response to his department's publication of a report into the quality of life of young people in England.

'Temptation'

Mr Balls highlighted concerns from parents about "tweenagers" who "are not yet teenagers but who have left childhood" - and says that early intervention is important for such youngsters who are beginning to go off the rails.

This is a time when children are moving from being children to becoming more self-reliant

"This is a time when children are moving from being children to becoming more self-reliant, more independent of the parents. It's the time when temptations are more on offer - when they're most likely to be pressured by peers, to start smoking cigarettes. These are the years when difficulties can begin," said Mr Balls.

Part of the problem is the difficult change from the supportive, family culture of a primary school to the more complex, less personal atmosphere of secondary school.

And this is accentuated by the lack of parental involvement in secondary school life.

"A common theme from parents is that while primary schools do well in engaging parents in their child's learning - that engagement often falls off in the early years of secondary school," says Mr Balls.

"Secondary schools say it is hard to engage parents - and parents say it is harder to be involved in schools."

Mr Balls wants secondary schools to become more parent-friendly and to find ways for parents to participate - such as inviting fathers to help with football training.

The report highlights that, compared to many other countries, young people in England spend an unusually large amount of time with other young people and away from their family.

Children start school at an earlier age in England than in many countries, spend longer hours in the classroom and then, as they get older, spend most of their spare time socialising away from adult influence.

These tweenagers, in need of parental support, find themselves shaped by the behaviour of their peer group instead.

"We need to put more focus on this tweenage group than we have done up to now," said Mr Balls.